I have a Vision Micosystems capacitive fuel probe which came installed in my partially completed kit. Since it is custom fit, I need to retain it. I understand I need a converter to change the VM capacitive output to 0-5v DC. While I have been told Princeton Electronics makes such a converter, I have not had a great deal of luck getting info from them. The info I got shows the converter needs to be calibrated with between 1 and 11 set points. I don not yet know why there is so much variation. If I do get a converter and go through the entire calibration procedure for the probe, do I then need to calibrate the Dynon as well? If so, that is an awful lot of fuel transfer. Is there another capacitive converter Dynon has been successful with?
Fuel probe vs EFIS calibration
- Thread starter skysailor
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- Mar 23, 2005
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You will need to calibrate the Dynon as well, after you do the Princeton. It's just the way it works. But you don't need to do 11 points with the Princeton, 2 should do fine. They allow 11 because many tanks aren't perfect boxes so they are non-linear in capacity vs. level, but the Dynon ends up taking care of this for you.
I don't know what the technical output of the VM sender is so I can't recommend any other converters. Princeton is the same company as GRT- have you tried calling them?
I don't know what the technical output of the VM sender is so I can't recommend any other converters. Princeton is the same company as GRT- have you tried calling them?
dodsond
New Member
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- Aug 9, 2006
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I e-mailed this guy and got exactly what I needed.
Todd Stehouwer [tstehouwer@sbcglobal.net]
I have not powered mine up, but the converters and compact and well made little jewels. The are a bit pricey but fit the bill perfectly.
It does look like a lot of fuel transfer to calibrate both the converters and the EMS, but that is hardly the hardest thing we have to do in building an airplane. You might do the calibration on scales to also get very accurate fuel tank CG info.
Todd Stehouwer [tstehouwer@sbcglobal.net]
I have not powered mine up, but the converters and compact and well made little jewels. The are a bit pricey but fit the bill perfectly.
It does look like a lot of fuel transfer to calibrate both the converters and the EMS, but that is hardly the hardest thing we have to do in building an airplane. You might do the calibration on scales to also get very accurate fuel tank CG info.
Thanks for the input. I got a first email response from Todd but have gotten no response to a follow up with a few other questions. Doing the fuel transfer on scales is a great idea which I had not thought about! I did plan to make the transfer work for me in that I will get the chance to put an inline filter at the output of each tank. Filtering all the fuel twice (once for each calibration) will have run about 130 gallons through and will give me a measure of confidence there is no fiberglass dust or other debris in the tanks.